View Single Post
mark houghton mark houghton is offline
Registered User
mark houghton's Avatar
Join Date: Jul 2008
Location: Central Washington State
Posts: 3,860
Originally Posted by fredmeister View Post
I know what your saying. Alot of issues with overboosting come up on the forum attributed to the elephant nose design of the typical GSF or B&B headers.

Of course this is part of the problem but I wonder if the wastegate leakage is another big factor. Its funny you found this in your case and I had a few instances last summer when I might have overboosted and nailed the overboost cutoff switch myself.

I have been wondering if the Tial has a different design that avoids this issue or do you think it was just the fact it was a new unit and everything is tight?
Did you ever take a look at the way Tial handles the valve stem and guide interface? I wonder if they run a seal on top to prevent leakage.

I will dig deeper and see what I can find on the forums.

It's been some time since I had the Tial apart so can't really remember how the design differs from stock. There's also an asbestos gasket between the body and bell of the stock WG that deteriorates over time (mine did) and can leak there as well.
You may have to search over on Rennlist as well...that might have been where I saw reference to the dude who had a machine shop make a guide for him.
Mark H. 1987 930, GP White, Wevo shifter, Borla exhaust, stock everything else. The result of a massive Pelicanite good will fire recovery effort. Truely an open book, ready for the slippery slopes to modification.
Old 03-15-2013, 04:52 AM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #4 (permalink)